We essentially take the corner down from the top layer, hide it away, undo the first move then we fetch this back symmetrically to reach the half-way point of the algorithm by swapping the corners on the top layer, finishing off with doing all this backwards. This algorithm has a lot of symmetry to it. Putting it all together, the sequence ( F D2 F' R' D2 R ) U2 ( R' D2 R F D2 F' ) U2 does what we want. Finally, when we fix the first two layers, we still need to turn U2 to undo the swap and the cube should be solved. This works because the rest of the top layer is unaffected by the planned moves. Similarly to how we previously did D2 and hid the corner, we now use U2 to swap the corner that is being turned. So before we undo any of those moves, let's move that corner out of the way again. Once again the simplest way to fix these two layers is to undo every move we've done so far: R' D2 R F D2 F', but of course this also restores the corner which we worked so hard to twist. We do however notice, that the top layer is looking better and it's only the first two layers that are in need of repair. Unfortunately, many pieces are still all over the place. Where are we now? We've found that using the moves F D2 F' R' D2 R we can turn the corner correctly in its place and not disturb quite as many pieces as just simply doing F R. This is even better as it anticipates the effect of the R and in a sense undoes it ahead of time. If we consider how it got there and imagine doing the same moves as a mirror image on R instead of F, we see that it can be fetched by R' D2 R as well. Maybe there is a better way to fetch the corner from its hiding spot. The cube is still messed up, but compared to just F R, some things are more to our liking, specifically the two pieces next to the corner that have yellow and blue on them. A short way is just to continue D2 R, undoing the hiding move and lifting the corner into its spot. To get the corner back we now have a few options. Now the front side is almost as it started and we've "hidden" our corner "behind" the cube. So to negate the unwanted effect of the first F turn, we want to incorporate a F' turn in our algorithm, but in a way that the corner we are manipulating doesn't go back to its starting spot. However, if we want to make some changes along the way, we can choose to not undo one of the moves, which can return many pieces back but not all. The simplest way to undo something that was done to the cube is to retrace the same moves backwards. How do we isolate the turning of just the corner we want? We notice that the corner turns into it's correct spot but obviously many other pieces are disturbed. Let's first attempt to just turn the yellow-blue-red corner in it's place without worrying about any of the other pieces. Start with blue facing front and yellow on top, as in the pictures. I'd like to explain a somewhat intuitive approach of turning these corners. Personally I would just stick with that you already know, by using your algorithm ( R U2 R' U' R U' R' L' U2 L U L' U L) twice. But it's shorter and therefore more efficient. I don't think it's particularly easy to remember. Perhaps holding it the same as above (Green front, Yellow top), and then use the following algorithm: L U L2 D L2 U' L F2 U' F2 U L2 D' This sequence of R' D' R D (2x) you will always have to do three or six times in order to orient all the corners.Īnd here is a video I made about a year ago explaining the entire Beginner's Method, including orienting the corners of the last layer.ĮDIT: Hmm, noticed you already know how to solve the corners, but are looking for a more efficient algorithm. So for your case above, put Green at the front and Yellow at the top, and use the following algorithm: R' D' R D (2x) In which case you can use a combination of R' D' R D (2x) sequences with setup moves to solve this. Personally I use the beginner's method when I solve my 3x3x3 Cube.
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